[Nosey]

as long as you don't abuse it (I have heard of people using it for their main internet and nothing was ever done, but you never know, it's in the fine print and they can invoke it at any time), you shouldn't have a problem, as long as you use one of the custom roms, all the ones I have tried have the fixes in them to the carrier thinks it's your phone doing the internet

I've actually been on a long distance trip (I work for an ambulance transport company) where I was in the back with a stable patient, hooked my laptop up to my phone and we watched some online movies, my average usage is probably under 500meg/day but I have had larger days, I think the most I had in a months time was around 10-15gig total usage

glad to of been some help